Reinforcing steel in concrete is normally protected from corrosion by the highly alkaline concrete medium. However, corrosion of the steel can occur as a result of contact with chlorides which enter the concrete matrix from external application of de-icing chemicals, or from marine waters. This corrosion process can be accelerated by the propagation of cracks in the concrete, which can lead to direct exposure of the steel to the corrosive action of the chlorides. This corrosive activity eventually results in the loss of integrity of the concrete structure. This form of concrete structural degradation is a common occurrence in many locations.
Thus, there is a need for new corrosion inhibiting admixtures which protect reinforcing steel from the action of corrosive chloride agents.